<template>
  <el-card class="box-card">
    <el-tree
      :data="data"
      show-checkbox
      default-expand-all
      node-key="id"
      ref="tree"
      highlight-current
      :props="defaultProps"
    >
    </el-tree>

    <div class="buttons">
      <el-button @click="getCheckedNodes">通过 node 获取</el-button>
      <el-button @click="getCheckedKeys">通过 key 获取</el-button>
      <el-button @click="setCheckedNodes">通过 node 设置</el-button>
      <el-button @click="setCheckedKeys">通过 key 设置</el-button>
      <el-button @click="resetChecked">清空</el-button>
    </div>
  </el-card>
</template>

<script>
export default {
  data() {
    return {
      checkNode: [], // 当前选中的节点
      data: [
        {
          id: 1,
          label: "一级 1",
          children: [
            {
              id: 4,
              label: "二级 1-1",
              children: [
                {
                  id: 9,
                  label: "三级 1-1-1",
                },
                {
                  id: 10,
                  label: "三级 1-1-2",
                },
              ],
            },
          ],
        },
        {
          id: 2,
          label: "一级 2",
          children: [
            {
              id: 5,
              label: "二级 2-1",
            },
            {
              id: 6,
              label: "二级 2-2",
            },
          ],
        },
        {
          id: 3,
          label: "一级 3",
          children: [
            {
              id: 7,
              label: "二级 3-1",
            },
            {
              id: 8,
              label: "二级 3-2",
            },
          ],
        },
      ],
      defaultProps: {
        children: "children",
        label: "label",
      },
    };
  },
  created() {
    this.checkNode = [1, 4, 9, 10, 2, 5, 6];
  },
  methods: {
    getCheckedNodes() {
      console.log(this.$refs.tree.getCheckedNodes());
    },
    getCheckedKeys() {
      console.log(this.$refs.tree.getCheckedKeys());
    },
    setCheckedNodes() {
      this.$refs.tree.setCheckedNodes([
        {
          id: 5,
          label: "二级 2-1",
        },
        {
          id: 9,
          label: "三级 1-1-1",
        },
      ]);
    },
    setCheckedKeys() {
      this.$refs.tree.setCheckedKeys([3]);
    },
    resetChecked() {
      this.$refs.tree.setCheckedKeys([]);
    },
  },
};
</script>

<style scoped lang="less">
.el-card {
  height: calc(100vh - 40px);
  text-align: center;
}
</style>
